1. Field of the Invention
The present invention relates to observation units used in an incubator, an isolator or the like. The incubator controls a culture environment in which cells are cultured, and the isolator is a device which includes a sterile space for biological or chemical work.
2. Description of Related Art
Conventionally, an incubator has been used as a device for culturing a sample such as a cell. However, in a conventional incubator, it is necessary to take out the sample from the incubator in order to observe condition of the sample under culture. However, the sample such as a cell is sensitive to temperature change, and therefore, when taken out from the incubator, the sample can be affected such that the cell is killed, for example.
In view of above problem, it has been proposed to provide the incubator with an observation device so that the condition of the sample can be observed with the sample being in the incubator. In this incubator, a projecting part is formed on an outer surface of a casing forming the incubator. In the projecting part, defined is a space in which the sample is to be placed for observation. The space is in communication with a space in the incubator. Also, the projecting part is provided with a window on top and bottom thereof each. Light can thereby pass through the space in the projecting part via the two windows on the top and bottom of the projecting part. On the outer surface of the casing, a microscope unit is arranged so as to sandwich the projecting part from upper and lower sides thereof.
With the incubator described above, it is possible to observe the sample under the environment in the incubator by moving the sample from the space in the incubator to the space in the projecting part. Therefore, it is not necessary to take out the sample from the incubator for observation of the sample.
However, the incubator described above is provided with the observation device (the microscope unit) on the outside thereof, resulting in an increase in size of the incubator. Also, the observation device is specific to the incubator described above, and therefore, it is difficult to apply the observation device to other incubators, resulting in low applicability.
For example, arrangement of the observation device in the incubator can be thought. However, if the conventional observation device is provided in the incubator without change, the observation device will be exposed to the environment in the incubator, and problems can be caused in an optical system or an imaging system of the observation device by moisture or the like.
Further, in the case of arranging the observation device in the incubator, the observation device needs to be automated and provided with a drive motor or the like for focusing. However, when being operated, the drive motor generates a large amount of heat, and the heat can be conducted to the sample and affect the sample.